The present invention relates to methods and apparatus for providing lighted areas on a glass or similar surface. More particularly, the present invention relates to those methods and apparatus that use polymer thick film (PTF) technology to selectively provide such lighted areas. Such methods and apparatus are used as back lighting of the glass or similar substrate or for animation of the lighted areas on the glass or similar substrate.
It is often quite useful to be able to provide light in a limited amount and over a limited area. Without meaning to limit the scope of the present invention, typical examples of such uses are with respect to night lights, the sources of light to set moods, and the back lighting of pictures or other materials.
It is often desirable to provide light in a limited amount and over a limited area. A discussion of the use of back lighting provides an illustration of a useful solution in such situations as well as the problems associated the current technology for treating circumstance such as those.
Back lighting is used to illuminate an illustration from behind. Such back light systems are used, for example, to set a mood in a room, to provide low-level lighting in a substantially darkened area such as a theater, or to display advertising at a point of sale. The illustration is mounted such that a light source is behind the illustration from the point of view of the observer. When the light source is turned off in a moderately dark environment, the illustration is generally not visible and when the light source is turned on, the observer can see the illustration clearly.
One technology for back lighting illustrations involves the use of an incandescent or fluorescent bulb in combination with a diffuser in an attempt to produce a relatively even distribution of light across the subject. Often, the diffuser causes a loss of light from the source and, usually, results in back lighting that is unevenly distributed. Generally, the light is brightest in the vicinity of the bulb and dimmer at the edges of the diffuser. Where the diffuser produces a relatively even distribution of light, the amount of light coming from the diffuser is significantly reduced from the amount originally emitted from the bulb. Further, back light systems that use bulbs often produce much heat that may damage the illustration over time.
Also, many current back light systems are relatively bulky. The light source and the diffuser are usually mounted in a box-like arrangement that occupies a significant amount of space. Such systems could not be subtly mounted on a wall; they would extend out from the plane of the wall so far as to generally disturb the aesthetic nature of the illustration. Further, the construction of such back light boxes is usually difficult and expensive.
There are back light systems that are not as bulky as the ones using incandescent or fluorescent lights. Polymer thick film thermoplastic materials have been applied to thin flexible substrates (such as Mylar(copyright) or polyester sheets) and used as backlights in, for example, wristwatches. The polymer thick film (PTF) thermoplastic inks tend to shrink and cause the flexible substrate to curl rendering it unsuitable for multiple layering which is a necessary trait for animated displays or back lights.
Thus, it is highly desirable to provide a system for producing light over a limited area where the system is characterized by compactness, simplicity of construction and economy of manufacture.
Therefore, it is an object of the present invention to provide an apparatus that will allow the production of light over a limited area.
It is a further object of the present invention to provide such an apparatus that is compact in construction.
It is an additional object of the present invention to provide such an apparatus that is simple to construct.
It is yet another object of the present invention to provide such an apparatus that is relatively inexpensive to manufacture.
Consideration of the specification, including the several figures to follow, will enable one skilled in the art to determine additional objects and advantages of the invention.
Having regard to the above and other objects and advantages, the present invention generally provides for an apparatus for providing lighted areas on a surface. The apparatus comprises a glass substrate having at least a first surface that includes a substantially clear substantially conductive layer, and a second surface that does not include a substantially clear substantially conductive layer. The present apparatus also includes a polymer thick film phosphor ink layer applied to the first surface of the glass substrate, a polymer thick film dielectric layer applied to at least a portion of the phosphor ink layer, and a polymer thick film conductive layer applied to at least a portion of the dielectric layer. It should be noted that the polymer thick film materials referred to in the present specification are polymer thick film thermoset materials. These thermoset materials are much more suitable for multi-layering than are polymer thick film thermoplastic materials. Further, the apparatus includes power connective means for connecting electrical power to the polymer thick film conductive layer and to the substantially clear substantially conductive layer of the glass substrate. When power is applied to the power connective means, the polymer thick film phosphor ink layer illuminates and light substantially shows through the second surface of the glass substrate.
In a preferred embodiment of the present invention, the polymer thick film conductive layer includes a material selected from the group consisting of copper, silver, gold, and carbon. In yet another preferred embodiment of the present invention, the power connective means is attached to at least a portion of the polymer thick film conductive layer by use of a solder connection, a conductive adhesive, compression of a conductive leaf spring on the polymer thick film conductive strip and the substantially clear substantially conductive layer, or compression of conductive rubber on the polymer thick film conductive strip and the substantially clear substantially conductive layer.
In a further preferred embodiment of the present invention, a polymer thick film nonconductive layer is applied to the polymer thick film conductive layer, the polymer thick film dielectric layer, the polymer thick film phosphor layer, and the glass substrate such that the nonconductive layer substantially insulates the polymer thick film conductive layer, the polymer thick film dielectric layer, the polymer thick film phosphor layer and the glass substrate from being touched by a user of the apparatus.
In addition, there is another preferred embodiment of the present invention wherein the glass substrate includes a layer having a design which is visible at least when power is applied to the power connective means such that, when power is applied to the power connective means, the polymer thick film phosphor ink layer illuminates and light substantially shows through the layer having a design which is visible at least when power is applied to the power connective means and through the second surface of the glass.
The present invention also provides for an apparatus for providing animated lighted areas on a surface. Such an apparatus comprises a glass substrate having at least a first surface that includes a substantially clear substantially conductive layer, and a second surface that does not include a substantially clear substantially conductive layer. The present invention also includes a polymer thick film phosphor ink layer applied to the substantially clear substantially conductive layer of the glass substrate, a polymer thick film dielectric layer applied to the phosphor ink layer, polymer thick film conductive strips applied to a plurality of portions of the polymer thick film dielectric layer and to at least a portion of the substantially clear substantially conductive layer of the glass substrate, and power connective means for connecting electrical power to the polymer thick film conductive strips associated with the polymer thick film dielectric layer and to the polymer thick film conductive strip associated with the substantially clear substantially conductive layer of the glass substrate. When power is applied to the power connective means, portions of the polymer thick film phosphor ink layer illuminate and light substantially shows through the second surface of the glass. Then the power is applied to and removed from the power connective means selectively and in such a sequence that the portions of the polymer thick film phosphor ink layer are illuminated and darkened to provide animation as seen through the second surface of the glass substrate.
In a preferred embodiment of the invention, the polymer thick film conductive strip includes a material selected from the group consisting of copper, silver, gold, and carbon. In yet another preferred embodiment of the invention, the power connective means is attached to at least a portion of the polymer thick film conductive strips by use of a solder connection, a conductive adhesive, compression of a conductive leaf spring on the polymer thick film conductive strip and the substantially clear substantially conductive layer, compression of conductive rubber on the polymer thick film conductive strip and the substantially clear substantially conductive layer. In another embodiment of the present invention, the apparatus further comprises a non-conductive layer applied to the polymer thick film conductive strips, the polymer thick film dielectric layer, the polymer thick film phosphor layer, and the glass substrate such that the non-conductive layer substantially insulates the polymer thick film conductive strips, the polymer thick film dielectric layer, the polymer thick film phosphor layer and the glass substrate from being touched by a user of the apparatus.
In another preferred embodiment of the present invention, the glass substrate also includes a layer having a design which is visible at least when power is applied to the power connective means such that, when power is applied to the power connective means, the polymer thick film phosphor ink layer illuminates and light substantially shows through the layer having a design which is visible at least when power is applied to the power connective means and through the second surface of the glass substrate.
Still other objects of the present invention will become apparent to those skilled in this art from the following description wherein there is shown and described a preferred embodiment of this invention, simply by way of illustration of one of the modes best suited to carry out the invention. As it will be realized, the invention is capable of other different embodiments and its several details are capable of modification in various, obvious aspects all without departing from the invention. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.